This application is to obtain funds to complete analysis of a case-control study of bladder cancer risk factors. The specific aims of the study are to: 1) test for an association between coffee consumption and bladder cancer; 2) test for an association between caffeine use and bladder cancer; 3) look for synergistic effects of coffee and caffeine with tobacco in relationship to bladder cancer risk; 4) determine why the incidence of bladder cancer is higher in the urban areas of Utah than the rural areas; 5) determine why the incidence of bladder cancer is increasing among older males in Utah; and 6) look for other variables that may be involved in the etiology of the disease. The coffee and caffeine variables are of interest to study since previous studies show inconsistent findings in terms of the association between those variables and bladder cancer. These hypotheses can be studied in Utah since only about 50% of the population have ever drunk coffee. Cases are identified through the Utah Cancer Registry (1978-1981) which registers all cases of bladder cancer diagnosed in the state of Utah. Controls aged 21-64 are selected by random telephone methods and those aged 65-84 are selected from the files of the Health Care Financing Administration. Home interviews are conducted by trained interviewers. Interviews will be completed by the end of 1981 on about 370 cases and 740 controls. This will represent a completion rate of about 85% of all eligible respondents. Analysis will be done using logistic regression models to control for multiple confounding variables while looking at single exposure variables. Odds ratios will estimate risk in this incidence-based study. Logistic regression models will be verified using stratified analysis. The Mantel-Haenszel test statistics will be used.